1. Field of the Invention
The present invention relates to a disc apparatus and, more particularly, to a disc apparatus used as a portable CD-ROM drive apparatus.
2. Description of the Related Art
Conventionally, a compact disc (12 cm or 8 cm diameter) which is referred to as a CD-ROM is used as a recording medium for storing information such as a database or software. In order to incorporate the CD-ROM into a miniaturized notebook type personal computer, a built-in type CD-ROM drive apparatus, which is incorporated into a housing, has been developed.
In a conventional disk apparatus, a tray for accommodating a disc is driven by a motor. The disc is placed on the tray when the tray is moved out of a housing of the disc apparatus. Then, the tray is returned to a position inside the housing by a drive force of the motor.
In the apparatus of a type in which the tray is moved by the motor, the motor for driving the tray and a transmission mechanism for transmitting a drive force to the tray are needed. This is an obstacle for reduction in size and thickness of the apparatus.
Japanese Laid-Open Patent Application No.7-235111 discloses a disc apparatus which eliminates a tray driving motor and a transmitting mechanism by manually moving the tray to a disc loading position within a housing or a disc changing position outside the housing.
In the above-mentioned patent document, since an optical pickup and a pickup drive motor are mounted on a bottom surface of the tray, the optical pickup and the pickup drive motor, which have a relatively large weight, are moved outside the housing in relation to the movement of the tray when the tray is drawn outside the housing. Accordingly, when the tray is drawn outside the housing, the center of gravity moves outside the housing, which results in an inclination of the entire apparatus in a direction of drawing the tray, i.e., the outward movement direction of the tray. Thus, there is a problem in that stability of the apparatus is lost.
Additionally, if the tray is inclined due to the movement of the center of gravity, the apparatus may wobble, and thus there is a problem in that a placing or removing operation of the disc is difficult.